Even though many of the criteria for personality disorders (PD) have either a negative bias or require an individual to possess insight into his or her own maladaptive behavior, few studies to date have examined whether informants may be a better source of information than the target of interest. Further, there is a dearth of research examining the nature of interpersonal impairment in marriage---the relationship most people find central to their lives. This study focuses on the differences between how husbands and wives describe each other in regard to pathological personality traits, and whether the presence of PD traits is related to marital satisfaction. A thorough battery of self-report and informant measures will be collected from each target and his or her spouse, as well as two knowledgeable informants per spouse. Additionally, measures of marital satisfaction, marital conflict, depression, anxiety, and substance abuse will be collected, and participants will complete two marital interaction tasks in the laboratory that will be coded for conflict and social support behaviors. The research questions to be examined in this study are critical not only for understanding the best method of assessing PD criteria, but also for understanding relationship formation and functioning among people with pathological personality traits.